DES加密文件

最新推荐文章于 2022-07-27 14:58:57 发布
原创最新推荐文章于 2022-07-27 14:58:57 发布 · 3.4k 阅读
1 ·
CC 4.0 BY-SA版权
文章标签：
#加密 #string #解密 #byte #initialization #stream
C# 专栏收录该内容
24 篇文章
订阅专栏
本文介绍了一种使用DES算法对文件内容进行加密和解密的方法，包括支持和不支持中文字符的两种情况。提供了生成随机密钥的功能，并详细展示了如何通过C#实现文件的加密与解密过程。
摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >
 /// <summary>
        /// 随机产生密钥
        /// </summary>
        /// <returns></returns>
        static string GenerateKey()
        {
            // Create an instance of Symetric Algorithm. Key and IV is generated automatically.
            DESCryptoServiceProvider desCrypto = (DESCryptoServiceProvider)DESCryptoServiceProvider.Create();

            // Use the Automatically generated key for Encryption. 
            return ASCIIEncoding.ASCII.GetString(desCrypto.Key);
        }
        
        /// <summary>
        /// DES加密文件内容(不支持中文)
        /// </summary>
        /// <param name="sInputFilename">输入文件名</param>
        /// <param name="sOutputFilename">输出文件名</param>
        /// <param name="sKey">加密密钥8位</param>
        public static void EncryptFileByASCII(string sInputFilename,string sOutputFilename,string sKey)
        {   
            FileStream fsInput = new FileStream(sInputFilename,FileMode.Open,FileAccess.Read);
            FileStream fsEncrypted = new FileStream(sOutputFilename,FileMode.Create,FileAccess.Write);

            DESCryptoServiceProvider DES = new DESCryptoServiceProvider();
            DES.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
            DES.IV = ASCIIEncoding.ASCII.GetBytes(sKey);
            ICryptoTransform desencrypt = DES.CreateEncryptor();
            CryptoStream cryptostream = new CryptoStream(fsEncrypted,desencrypt,CryptoStreamMode.Write);

            byte[] bytearrayinput = new byte[fsInput.Length];
            fsInput.Read(bytearrayinput, 0, bytearrayinput.Length);
            cryptostream.Write(bytearrayinput, 0, bytearrayinput.Length);
            cryptostream.Close();
            fsInput.Close();
            fsEncrypted.Close();
        }
        /// <summary>
        /// DES解密文件(不支持中文)
        /// </summary>
        /// <param name="sInputFilename">输入文件名</param>
        /// <param name="sOutputFilename">输出文件名</param>
        /// <param name="sKey">解密密钥8位</param>
        public static void DecryptFileByASCII(string sInputFilename, string sOutputFilename, string sKey)
        {
            DESCryptoServiceProvider DES = new DESCryptoServiceProvider();
            //A 64 bit key and IV is required for this provider.
            //Set secret key For DES algorithm.
            DES.Key = ASCIIEncoding.ASCII.GetBytes(sKey);
            //Set initialization vector.
            DES.IV = ASCIIEncoding.ASCII.GetBytes(sKey);

            //Create a file stream to read the encrypted file back.
            FileStream fsread = new FileStream(sInputFilename,FileMode.Open,FileAccess.Read);
            //Create a DES decryptor from the DES instance.
            ICryptoTransform desdecrypt = DES.CreateDecryptor();
            //Create crypto stream set to read and do a 
            //DES decryption transform on incoming bytes.
            CryptoStream cryptostreamDecr = new CryptoStream(fsread,desdecrypt,CryptoStreamMode.Read);
            //Print the contents of the decrypted file.
            StreamWriter fsDecrypted = new StreamWriter(sOutputFilename);
            fsDecrypted.Write(new StreamReader(cryptostreamDecr).ReadToEnd());
            fsDecrypted.Flush();
            fsDecrypted.Close();
        }
        /// <summary>
        /// 对文件内容进行DES加密(支持中文)
        /// </summary>
        /// <param name="sourceFile">待加密的文件绝对路径</param>
        /// <param name="destFile">加密后的文件保存的绝对路径</param>
        /// <param name="sKey">加密密钥8位</param>
        public static void EncryptFileByUnicode(string sourceFile, string destFile,string sKey)
        {
            if (!File.Exists(sourceFile))
            {
                throw new FileNotFoundException("指定的文件路径不存在！", sourceFile);
            }
            byte[] btKey = Encoding.Default.GetBytes(sKey);
            byte[] btIV = Encoding.Default.GetBytes(sKey);
            DESCryptoServiceProvider des = new DESCryptoServiceProvider();
            byte[] btFile = File.ReadAllBytes(sourceFile);
            using (FileStream fs = new FileStream(destFile, FileMode.Create, FileAccess.Write))
            {
                try
                {
                    using (CryptoStream cs = new CryptoStream(fs, des.CreateEncryptor(btKey, btIV), CryptoStreamMode.Write))
                    {
                        cs.Write(btFile, 0, btFile.Length);
                        cs.FlushFinalBlock();
                    }
                }
                catch
                {
                    throw;
                }
                finally
                {
                    fs.Close();
                }
            }
        }
        /// <summary>
        /// 对文件内容进行DES加密，加密后覆盖掉原来的文件(支持中文)
        /// </summary>
        /// <param name="sourceFile">待加密的文件的绝对路径</param>
        /// <param name="sKey">加密密钥8位</param>
        public static void EncryptFileByUnicode(string sourceFile, string sKey)
        {
            EncryptFileByUnicode(sourceFile, sourceFile, sKey);
        }
        /// <summary>
        /// 对文件内容进行DES解密(支持中文)
        /// </summary>
        /// <param name="sourceFile">待解密的文件绝对路径</param>
        /// <param name="destFile">解密后的文件保存的绝对路径</param>
        /// <param name="sKey">解密密钥8位</param>
        public static void DecryptFileByUnicode(string sourceFile, string destFile, string sKey)
        {
            if (!File.Exists(sourceFile)) throw new FileNotFoundException("指定的文件路径不存在！", sourceFile);
            byte[] btKey = Encoding.Default.GetBytes(sKey);
            byte[] btIV = Encoding.Default.GetBytes(sKey);
            DESCryptoServiceProvider des = new DESCryptoServiceProvider();
            byte[] btFile = File.ReadAllBytes(sourceFile);
            using (FileStream fs = new FileStream(destFile, FileMode.Create, FileAccess.Write))
            {
                try
                {
                    using (CryptoStream cs = new CryptoStream(fs, des.CreateDecryptor(btKey, btIV), CryptoStreamMode.Write))
                    {
                        cs.Write(btFile, 0, btFile.Length);
                        cs.FlushFinalBlock();
                    }
                }
                catch
                {
                    throw;
                }
                finally
                {
                    fs.Close();
                }
            }
        }
        /// <summary>
        /// 对文件内容进行DES解密，加密后覆盖掉原来的文件(支持中文)
        /// </summary>
        /// <param name="sourceFile">待解密的文件的绝对路径</param>
        /// <param name="sKey">解密密钥8位</param>
        public static void DecryptFileByUnicode(string sourceFile, string sKey)
        {
            DecryptFileByUnicode(sourceFile, sourceFile, sKey);
        }